1914
January-February: Rönnebeck's c1912 bronze Head of Marsden Hartley is shown in the "Exhibition of Paintings by Marsden Hartley of Berlin and New York" at Alfred Stieglitz's Gallery 291 in New York, New York.

1914-1918
Serves as an officer in the German Imperial Army. Receives Iron Cross First Class, Iron Cross Second Class and the Cross of Hanseates. Injured in the line of duty in the Battle of the Marne, France in 1915. Upon release from the hospital, continues to serve until the end of the war.

1914
Returns to Berlin.

1920-1921
Travels throughout Italy with German writer Max Sidow and German poet Theodor Daubler. Executes a series of drawings and lithographs of Positano and the Amalfi Coast.

April-May: Over sixty pieces including sculpture, drawings and lithographs in solo exhibition at Weyhe Gallery, New York. “Sculpture, Drawings and Lithographs by Arnold Rönnebeck".

July: Travels to Taos, New Mexico to stay as the guest of Mabel Dodge Luhan at her ranch, Los Gallos. Executes a series of drawings, watercolors and lithographs of Southwestern themes. Meets artist Louise Harrington Emerson (1901-1980).

October 1925-February 1926: Travels to Omaha, Nebraska to execute Grief, a monument for the Mengedoht family. Executes several portrait busts of prominent Omaha citizens. Exhibits eight sculptures at the Omaha Society of Fine Arts.

1926

March: Marries Louise Harrington Emerson in New York. The couple travels throughout the west with stops in San Diego, Los Angeles and Denver.

Completes six terracotta panels entitled The History of Money for the mezzanine of the Denver National Bank, Denver, Colorado.

Receives gold medal from the Kansas City Art Institute for his lithograph, The Atlantic.

1929
March-September: The Dancer included in Ralph T. Walker's exhibit, "Man's Study for a Country House" at The Architect and Industrial Arts Exhibition of Contemporary American Design, The Metropolitan Museum of Art, New York, New York.

May: Daughter Annamarie Ursula Ronnebeck born.

June-August: Sails to Germany with Louise on the S.S. Dresden, returns on the Hamburg Amerika Line.

Completes reredos entitled The Ascension for the Church of the Ascension, Denver, Colorado.

May-June: Exhibits Wall Street in The Exhibition of Contemporary American Prints at the Victoria and Albert Museum, London, England.

June: Resigns as Director of the Denver Art Museum.

December: Exhibits lithograph, From the Tribune Tower at the Second International Exhibition of Lithography and Wood Engraving at the Art Institute of Chicago, Chicago, Illinois.